'''
条件控制语句
'''
a, b = 1, 2
# while a<10 :
#     print(a)
#     a,b=b,a+b

if a < 1:
    print("aa")
elif a < 3:
    print(b)
# for
str = ["C", "C++", "Perl", "Python"]
for x in str:
    print(x, end=',')
for i in range(len(str)):
    print(i, str[i])
print(list(range(100)))

